docs: def _security_auth_headers(self, username, password, headers):
          """
          Add in the requisite HTTP Authentication Headers
  
          :param username: Riak Security Username
          :type str
          :param password: Riak Security Password
          :type str
          :param headers: Dictionary of headers
          :type dict
          """
          userColonPassword = username + ":" + password
          b64UserColonPassword = base64. \
              b64encode(str_to_bytes(userColonPassword)).decode("ascii")
          headers['Authorization'] = 'Basic %s' % b64UserColonPassword